Nepal, Nov. 2 -- pring gives way to a rainy monsoon, and then autumn arrives in a quiet, spectacular way. Apple orchards are heavy with fruit below a rugged trans-Himalayan landscape.

For tourists who flock to Mustang in this season, this is a breathtaking sight. For locals, however, apple trees sagging with fruit tell a story of climate uncertainty, shifting livelihoods, and demographic change unfolding in the mountains of Nepal.

Apples were always central to Mustang's economy and identity, and this more true today than ever before. Cultivation has gradually expanded to higher elevations as temperatures rise and precipitation patterns change.

"Apple cultivation has prospered in these upper areas now. Earlier it was good mostly around...